Tag: ESX

GestaltIT, VAAI, vCloud Director, Virtualization, VMware, VMworld, vSphere

vSphere 5, it’s here! What’s new?

Bas Raayman

It’s here, it’s here. 😉

VMware just announced their new version of vSphere 5, and as you have probably found out, general availability is targeted toward August this year. There is a whole bunch, and I mean a whole bunch, of new stuff coming out, and everyone knows what we can expect at VMworld this year.

Let me be clear that this post is in no way trying to sum up all the new things that are introduced with vSphere 5, but this is mean to give you a quick and easy to consume overview of some of the major new features.

Key stuff that is new or has changed in vSphere 5:

  • Virtual hardware limits. We can now address 32 virtual CPUs and a maximum of 1TB of RAM (note that virtual machine hardware type 8 is required). We see people running larger and larger workloads, and are seeing more and more people moving their tier 1 applications to a virtualized environent. Anyone who has tried to virtualize a large database or business warehouse system will know what I mean.

    One word of caution though. Even though we can now create very large installations, be careful. This is not a sensible size for all applications, and you should check on an application specific basis if you really need something this big, and are able to leverage all of the resources it offers.

  • VMFS version 5. With the updated version of the VMFS there are some modifications being made. For one, you no longer need to use extents to create volumes over 2TB in size, and they have added support for physical RDMs that are over 2TB.
  • The service console is missing. Well, it's not really missing, but there is no more service console, due to the fact that you will now only find ESXi as the hypervisor. Although some people might be missing some things without the traditional ESX service console, this does offer some advantages like having only a single vSphere package, hardened security and less patches. But this should probably be one of the changes that almost everyone has seen coming, so I'm not going to go in to the depths on the pros and cons of this choice.
  • VAAI has again been enhanced. With vSphere 5, there are enhancements for both block and file based storage:
    • for block:
      • Thin provision stun has been added, which is basically an option to get feedback when a thinly provisioned LUN is full. You will now get a message back from the array, and the affected guests are “stunned”. This allows the admin to add some more free space to the LUN, after which the guests can resume normal operation.
      • Space reclaim is the second feature that has been added. Now, one caveat is that this hardware offload is dependent of VMFS version 5. Anything prior to that won’t do the job. If that prerequisite is in place, any blocks that are freed up by VMFS operations, things like VM deletion or snapshot deletion, will now return their blocks to the pool of free blocks.
    • For file:
      • You can now use NFS full copy. Somewhat similar to the block version, copying of files can now be offloaded to the array, which of course should speed up things like clone creation.
      • Extended stats adds the ability to get the extended information from files. Information about actual space allocation or the fact if the file is deduplicated can now be retrieved.
      • We can now use space reservation, to actually pre-initialize a disk and allocate all of the required space right off the bat.
  • VMware has redesigned HA. The new architecture should help people who want to work with streched clusters.

    Basically, VMware has moved away from underlying EMC Autostart based construct to an entirely new model. The HA agent is now called the FDM, and one of the nodes in the cluster will now take on the role of master. All of the remaining nodes in the cluster are slaves to this master, which means that we are no longer using the primary/secondary concept that was common with the previous version of HA. During normal operation, we should only see one master node per cluster.

    Benefits of the new construct are that we are no longer that susceptible to DNS issues. Also, VMware has added additional communication paths, -we can now also leverage so called “Heartbeat datastores”-, that will aid us in the detection of failures. And, as a bonus VMware has also added support for IPv6.

    Since the entire HA stack has been rewritten, there are a lot of changes coming, and I’m planning on getting down to the nitty gritty in a future post, and I’m sure that my friend Duncan will also be explaining this in great detail on his blog.

  • VASA, or “vSphere Storage API for Storage Awareness” is basically a way for the storage array to actually tell vSphere what it can do, or what it is currently doing. Imagine getting feedback if your storage is cable of VAAI. Or something more simple like telling vSphere what RAID level a datastore has. Sounds sensible right? Now combine that with the new Storage DRS in vSphere 5, and you get a pretty good picture of what VASA can help you with.
  • Storage DRS. The DRS feature in vSphere is already pretty well known, and it’s something that I see in use a lot at customer sites.

    Well, now you can also use DRS for your storage. To enable this feature, you create a so called “datastore cluster”, which is in essence nothing more than several datastores combined. Now, when you create a new VM, it is placed inside of a datastore cluster, and storage DRS balances everything out based on some key criteria like space utilization and I/O latencies. More to follow in a different post.

Now, this is by no means a complete overview, and I’ll be going in to these an other new features in upcoming posts. And I don’t want to flood you with information that can also be found on plenty of other blogs out there, but this should give you a good start. Look back for the things mentioned up here, but also for things like the added support for software based FCoE initiators, APD / PDL, the vSphere storage appliance, the new SRM 5 or vCloud Director 1.5.